014.5BILLION YEARS AGO
PLANET FORMS
Earth takes shape.
Earth formed from material orbiting the young Sun. The early planet was hot, frequently struck by other bodies and radically different from the stable world we recognize today.
SEEKGLOBE · EARTH THROUGH TIME
Follow the Earth timeline from the planet’s formation about 4.5 billion years ago through the first evidence of life, rising oxygen, complex animals, supercontinents, mass extinction, humans and the world we know today.
01 · EARTH TIMELINE
The dates below are rounded landmarks, not the only important events in Earth history. They give the scale needed to understand how slowly geology changes — and how recently human history appears.
PLANET FORMS
Earth formed from material orbiting the young Sun. The early planet was hot, frequently struck by other bodies and radically different from the stable world we recognize today.
EARLY LIFE
Some of the earliest evidence associated with life dates to roughly this period. For billions of years, life remained microscopic while the planet’s oceans, crust and atmosphere continued to change.
GREAT OXIDATION EVENT
Atmospheric oxygen rose dramatically during the Great Oxidation Event, reshaping Earth’s chemistry and opening new evolutionary possibilities for life.
CAMBRIAN PERIOD
The fossil record shows a major diversification of animal life around the beginning of the Cambrian Period, when many important body plans became established.
PANGAEA
Earth’s major landmasses came together into Pangaea. Later plate movement split that supercontinent apart and helped shape the continents shown on modern maps.
MASS EXTINCTION
A major mass extinction eliminated the non-avian dinosaurs and many other groups. Mammals later diversified into ecological roles that had become newly available.
HOMO SAPIENS
Homo sapiens emerged only in the final fraction of Earth’s immense history. Human civilization occupies an even thinner slice of the timeline.
PLANET EARTH TODAY
Plate tectonics continues, climates shift, coastlines move and ecosystems evolve. Today’s continents, ocean basins and travel landscapes are temporary states in a much longer planetary story.
02 · DEEP TIME
If Earth’s 4.5-billion-year history were compressed into one 24-hour day, modern humans would appear only in the final seconds. That scale is the central idea behind any useful Earth timeline.
03 · MAJOR CHAPTERS
Geologists divide deep time into formal units. This simplified four-part view is designed for orientation: from a young planet to complex life and, finally, the extremely recent human world.
Earth forms, heats, differentiates internally and develops an early crust while impacts remain common.
Stable crustal regions develop and early life is present in a world with an atmosphere very different from today’s.
Atmospheric oxygen rises, eukaryotic life evolves and multicellular organisms eventually become more widespread.
Animal and plant life diversifies dramatically across oceans and continents, through extinctions, tectonic change and changing climates.
04 · A MOVING PLANET
The world map feels fixed only because human lives are short. Over geological time, tectonic plates carry continents across the planet, open and close ocean basins, raise mountains and rearrange coastlines.
Much of Earth’s land joined into one supercontinent.
The familiar modern geography is one temporary arrangement.
05 · WHY THE EARTH TIMELINE MATTERS
Ranges rise through tectonic processes and are then worn down by weather, ice and rivers.
Sea level, erosion, sediment and tectonics continually reshape the boundary between land and water.
Present-day geography is one frame in a movie measured in millions of years.
Cities, borders and recorded history occupy only the final instant of the planet’s timeline.
06 · EARTH TIMELINE FAQ
Earth is about 4.5 billion years old. Scientific estimates are based on radiometric dating of ancient rocks, meteorites and other early Solar System material.
Evidence associated with very early life extends back more than 3.5 billion years, with some evidence and interpretations reaching toward roughly 3.8 billion years ago.
The Great Oxidation Event marks a major rise in atmospheric oxygen, changing Earth’s surface chemistry and the conditions under which life evolved.
A major diversification of animal life appears in the fossil record around the beginning of the Cambrian Period, roughly 541 million years ago.
Pangaea assembled during the late Paleozoic Era and was largely together around 300 million years ago before beginning to break apart later.
Homo sapiens appeared only around 300,000 years ago — an extremely recent moment compared with Earth’s approximately 4.5-billion-year history.
KEEP EXPLORING
See the planet through scale, water, atmosphere and other defining facts.
Explore Earth → ATLAS · LANDMove from geological time to the major land regions of the present-day world.
Open atlas → ATLAS · WATERExplore the five named ocean basins that cover most of Earth’s surface.
Explore oceans →